1. Field of the Invention
The present invention relates to a package bag enclosing various objects to be packed, particularly hermetically enclosing foods and seasonings, and also relates to a packaging device, which continuously form such a package bag while enclosing the objects to be packed in the package bag.
2. Discussion of Background
A conventional technique discloses a rectangular package bag, made of a fusion-bondable film, in which an object to be packed is enclosed by thermally sealed portions, provided along three sides or four sides, under a state that the object to be packed is enclosed in an inside of the package bag.
When a sealant layer, which is fusion-bonded so that interfacial peeling, ply separation, or cohesive failure can occur, is formed in an inside of the film configuring this kind of the package bag, it is possible to take the object to be packed out of the package bag by pulling portions of the film on both sides of the package bag so as to break the thermally sealed portion without cutting the package bag.
However, even though the sealant layers, thermally sealed so as to occur the interfacial peeling or the like, are provided in the inside of the film configuring the package bag so that the sealant layer of a film forming a surface of the package bag and the sealant layer of a film forming another surface of the package bag are fusion-bonded in the thermally sealed portion, a sufficient force should be applied to open the package bag since there is a tendency that a tensile force to the films is uniformly applied to entirely of the thermally sealed portion, which is simply formed. Although it is possibly to adopt a method of forming the thermal seal so as to cause the interfacial peeling or the like with a relatively small force, it is difficult to stably maintain an enclosed state of the object to be packed.